We might all know Zeiss for their camera lenses, but they also have a big business in microscopes too. Not long ago work got one, but only recently did they get the DSLR attachment for it. I only had a very quick play with it.

There's a big rotating control for magnification, and you adjust focus by moving the distance. Of course, I had to put it to maximum and see what you get. Doing the ruler test, I got a maximum photographic magnification of 2.5x. The interesting thing there is that the working distance I measured to be 30cm! I can only dream of that on a photographic lens. I don't know what the effective focal length or aperture is. I think it is in diffraction limiting at that point.

Shall have to find some time to play with it more, but it is used regularly for work...

Zeiss and Leica are big in microscopy. I've used them quite a lot during my research, including some really nice confocal stuff. Mostly it was very young fish, fish scales and the cells on the scales. (It's great fun to see cells dividing.)

Never got a chance to use the D700 from the lab though. That would have been great.

Pentax is also known for microscopy,I've even noticed Pentax branded microscopes in NG & Discovery documentaries.
It would be amazing to use a DSLR attached to a microscope,one could get the best macros ever.

Due to the nature of where I work, the one they have is configured for relatively low magnification. As mentioned above, only 2.5x optical when it gets to the DSLR. I believe it was chosen for its working distance than anything else...